Enable Flow Strict

src/components/Layout/Layout.js

@@ -1,4 +1,4 @@
-// @flow
+// @flow strict
 import React from 'react';
 import Helmet from 'react-helmet';
 import type { Node as ReactNode } from 'react';

src/components/Layout/Layout.test.js

@@ -1,4 +1,4 @@
-// @flow
+// @flow strict
 import React from 'react';
 import renderer from 'react-test-renderer';
 import Layout from './Layout';

src/components/Layout/index.js

@@ -1,2 +1,2 @@
-// @flow
+// @flow strict
 export { default } from './Layout';